Spring clip to retain a honing stone in the tool body



R. C. ENGLE April 9, 1963 SPRING CLIP TO RETAIN A HONING STONE IN THE TOOL BODY Filed Feb. 20, 1961 F0167? C. E, BY by D wa /s United States Patent ()filice 3,084,487 Patented Apr. 9, 1953 3,884,487 SPRING CLL? T RETAHN A HGNING STONE IN THE TOOL BGDY Robert C. Engle, Livonia, Mich, assignor to Micromatic Hone Corporation, Detroit, Mich, a corporation of Michigan Filed Feb. 20, 1961, Ser. No. 98,552 (Ziaims. (Cl. 51-1843) This invention relates to honing tools and particularly to a honing tool having new and improved means for retairiling the honing stones in assembled relationship therewit The structure of the present invention is particularly adapted for use in small size honing tools in which a minimum amount of space is available and in which garter springs or other bulky means may not be feasibly utilized for retaining the honing stones in assembled relationship with the honing tool. Honing tools and honing stones which omit the use of garter springs or the like are not new and an example of the same may be found in United States Patent No. 2,467,094. The honing stone disclosed in said patent is adapted to be frictionally engaged in the slot of the honing tool body. While this type of honing stone has gained wide commercial acceptance, it has nonetheless been subject to certain faults, particularly with reference to the retention of the honing stones in a Warm tool. It has been found that an abrasive action occurs between the sides of the honing stone and the adjacent side walls of the slot within which it is retained, producing an enlargement of the slot. Thus, when a rotating honing tool is removed from a workpiece, centrifugal force throws the honing stones out of their respective slots.

Accordingly, it is an object of the present invention to provide a honing tool having new and improved means for retaining the honing stones in assembled relationship with the honing tool despite enlargement of the slots of the honing tool body.

It is another object of the present invention to provide a honing tool of the above character which is inexpensive of manufacture, which does not require modification of the honing tool body, and which may be produced with only slight modification of the parts of many presently used honing tools.

It is another object of the present invention to provide a honing tool of the above character which is convenient to use, which is sturdy in construction and which results in improved efiiciency and accuracy of the honing operation.

These and other objects of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a fragmentary elevational view, partly in section, of a honing tool embodying the principles of the present invention;

FIG. 2 is a fragmentary sectional view of the structure illustrated in FIG. 1, taken along the line 2-2 thereof;

FIG. 3 is a fragmentary sectional view of the structure illustrated in FIG. 1, taken along the line 3-3 thereof;

FIG. 4 is a fragmentary sectional view of a honing tool embodying a modified form of the present invention, taken along the line 4-4 of FIG. 6;

FIG. 5 is a sectional view of the structure illustrated in FIG. 4, taken along the line 55 thereof; and

FIG. 6 is a sectional view of the structure illustrated in FIG. 4, taken along the line 66 thereof.

Referring now to the embodiment of the invention illustrated in FIGS. 1-3, the honing tool of the present invention includes a hollow body member 10 of generally tubular shape and having a plurality of angularly spaced, radially open slots, one of which is illustrated at 12. The

slot 12 will be seen to be elongated in a direction longitudinally or axially of the tool and is open at both the inner peripheral wall 14 and outer peripheral wall 16 of the body 10. Abrasive elements or honing stones are confined Within the slots of the tool body for radially outward feed movement and one such stone 18 is shown within the slot 12. The stone 18 is of a well-known type and includes a bonded absasive stick 20 encased within a plastic shell 22, so that the stick 20 is exposed on the working face 24 thereof, which faces in a radially outward direction. The rear wall 26 of the shell 22 is flat and lies in a plane inclined relative to the axis of rotation of the tool. The tool body is adapted to be rotated by a suitable drive shaft (not shown) about and reciprocated along its central longitudinal axis while the stones are fed into abrading contact with the work surface. The thrust and torque forces developed on the stones are absorbed by the body 10 at the walls defining the stone supporting slots.

A honing stone expansion member 28 is snugly but slidably disposed within the body 10 and has a circular cylindrical outer periphery 30 engageable with the inner Wall 14 of the body 10. The expansion member 28 is provided with a plurality of cam slots adapted to be radially aligned with the body slots. One of such slots is illustrated at 32 in alignment with the body slot 12. The slot is provided with opposite parallel side walls 34 and 36 and a bottom cam surface 38 inclined with respect to the longitudinal axis of the tool and adapted to conformably engage the rear wall 26 of the honing stone 18. A groove 40 is formed in the outer periphery 30 of the expansion member 28 adjacent the slot side wall 34. The groove 40 has a bottom Wall 42 and a shoulder 44 and is intended to accommodate a spring wire clip 46. The spring element 46 consists primarily of an arm portion 48 having a central projection 50' engageable with the shoulder 44 and merging into short inclined portions 52 at the opposite ends thereof which, in turn, are connected to portions 54 lying along the shoulder 44. A pair of projections 56 are formed at the opposite ends of the wire clip and seat in holes 58 which are drilled through the groove bottom wall 42 into the expansion member 28. The holes 58 are inclined toward the honing stone 18, so that when the honing stone is inserted into the slot 32, a force will be applied to the prongs 56, tending to maintain them seated within the holes 58. The arm portion 48 is spaced away from the shoulder 44 and is adapted tobe compressed in a direction toward the shoulder 44 upon insertion of the honing stone 18 through the slot 12 and into the slot 32. Thus, the arm 48 wedges the stone against the opposite slot side wall 36 and will retain the stone in assembled relationship with the tool despite enlargement of the honing tool body slot 12 as a result of wear.

FIGS. 4-6 illustrate a modified form of the invention in which a tubular honing tool body 60 is illustrated as having a radially open slot 62. in the wall thereof adapted to carry and drive in rotation a honing stone 64. A honing stone expansion member on is disposed within the body 68 and is provided with a recess 63 having opposite side walls 78 and 72 and an inclined bottom wall 74. Recess 68 is intended to be radially aligned with the body slot 62, in order to receive the rear portion of the honing stone 64.

As may be seen in FIG. 5, the recess side wall 78 is aligned with one side wall 76 of the slot '62, whereas the recess side wall 72 is recessed in back of the side wall 78 of the slot 62, thus providing the recess 68 with a greater width than the slot 62, said greater Width being required in order to accommodate the spring arm 80 of a spring element 82 which has a flange portion 84 lying flatly against the recess bottom wall 74 and secured thereto by a screw 86. As may be seen in FIG. '6, the spring arm 80 is of generally triangular shape, is disposed parallel to the side walls 78 and 72 of the recess for the major portion of its length and is spaced from but lies adjacent to the side wall '72 for the major portion of its length. The arm 8i} is angularly bent at the opposite ends thereof to provide inclined portions 88 and $3 which terminate in flat shoulder portions 92 and 94, respectively, engaging the side wall 72. When the honing stone 6 is inserted through the body slot 62 and into the recess d3, it will contact the arm portion 37 on one side thereof to spring lead the inclined portions 88 and 96' and to cause the stone 64 to be wedged between the arm 80 and the opposite recess side wall 70-. As the arm 8t! is spring loaded, the terminal portions 92 and 94 of the arm 3t! slide in opposite directions along the side wall with the deflection of the inclined portions 88 and 90.

In both embodiments of the present invention, the spring element will slide axially along the side of the honing stone as the expansion member is adjusted, but the spring element does not move radially with the stones. The spring applies a gripping force to the stones which is surhcierit to hold them in the tool despite an oversize or worn tool body slot.

While it will be apparent that the preferred embodiments herein illustrated are well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. A honing tool including a hollow body member adapted to be driven in rotation and having a radially open slot adapted to receive a honing stone for radially outward feed movement, a honing stone expansion member in said body member having a recess adapted to be aligned with said slot, said honing stone expansion member being axially movable relative to said body member, said recess having opposite side walls and a bottom surface inclined relative to the axis of rotation for producing radial feed movement of the honing stone upon axial movement of said expansion member relative to said body member, a spring element adjacent one side wall of said recess slidably and yieldably engageable with the side wall of a honing stone for frictionally gripping the honing stone and means connecting said spring to said expansion member to prevent axial and radial movement of said spring relative to said expansion member.

2. A honing tool including a hollow body member adapted to be driven in rotation and having a radially open slot adapted to receive the honing stone for radially outward feed movement, a honing stone expansion memher in said body member having a recess adapted to be aligned with said slot, said honing stone expansion member being axially movable relative to said body member, said recess having opposite side walls and a bottom surface inclined relative to the axis of rotation for producing radial feed movement of the honing stone upon axial movement of said expansion member relative to said bodv member, said expansion member having a shoulder adiacent one recess side Wall thereof spaced from said one side wall in a direction away from the other of said side walls, a spring wire engaging said shoulder and engageable with one side of a honing stone seated in said recess to yieldably bias said stone toward said other recess side wall, and means connecting said spring wire to said expansion member to prevent axial and radial movement of said spring wire relative to said expansion member.

3. A honing tool including a hollow body member adapted to be driven in rotation and having a radially open slot adapted to receive a honing stone for radially outward feed movement, a honing stone expansion member in said body member having a reces adapted to be aligned with said slot, said honing stone expansion member being axially movable relative to said body member, said recess having opposite side walls and a bottom surface inclined relative to the axis of rotation for producing radial feed movement of the honing stone upon axial movment of said expansion member relative to said body member, said expansion member having a pair of spaced holes therein adjacent one of said recess side walls, and a spring wire having the ends thereoi seated in said holes for axial movement with said expansion member, said spring wire being engageable with a honing stone disposed in said recess to bias said honing stone in a direction toward the other of said recess side walls.

4. A honing tool including a hollow body member adapted to be driven in rotation and having a radially open slot adapted to receive a honing stone for radially outward feed movement, a honing stone expansion memher in said body member having a recess adapted to be aligned with said slot, said honing stone expansion member being axially movable relative to said body member, said recess having opposite side walls and a bottom surface inclined relative to the axis of rotation for producing radial feed movement of the honing stone upon axial movement of said expansion member relative to said body member, said expansion member having a recessed shoulder adjacent one side wall of the recess thereof and a pair of spaced holes intermediate said shoulder and said one side Wall, a spring wire having the ends thereof seated in said holes for axial movement with said expansion member and having a projection engageable with said shoulder, said spring being adapted to engage a honing stone seated in said recess and bias the same in a direction toward the other of said recess side walls.

5. A honing tool including a hollow body member adapted to be driven in rotation and having a radially open slot adapted to receive a honing stone for radially outward feed movement, a honing stone expansion member in said body member having a recess adapted to be aligned with said slot, said honing stone expansion member being axially movable relative to said body member, said recess having opposite side walls and a bottom surface inclined relative to the axis of rotation for producing radial feed movement of the honing stone upon axial movement of said expansion member relative to said body member, and a spring element having a flange portion fixedly secured to said expansion member in said recess, said spring element having a spring arm provided with inclined end portions engageable with one of the recess side walls of said expansion member, said end portions being flexible and said spring arm being operable to yieldingly bias a honing stone seated in said recess against the other of said recess side walls.

References Cited in the file of this patent UNITED STATES PATENTS 1,886,584 Prange Nov. 8, 1932 

1. A HONING TOOL INCLUDING A HOLLOW BODY MEMBER ADAPTED TO BE DRIVEN IN ROTATION AND HAVING A RADIALLY OPEN SLOT ADAPTED TO RECEIVE A HONING STONE FOR RADIALLY OUTWARD FEED MOVEMENT, A HONING STONE EXPANSION MEMBER IN SAID BODY MEMBER HAVING A RECESS ADAPTED TO BE ALIGNED WITH SAID SLOT, SAID HONING STONE EXPANSION MEMBER BEING AXIALLY MOVABLE RELATIVE TO SAID BODY MEMBER, SAID RECESS HAVING OPPOSITE SIDE WALLS AND A BOTTOM SURFACE INCLINED RELATIVE TO THE AXIS OF ROTATION FOR PRODUCING RADIAL FEED MOVEMENT OF THE HONING STONE UPON AXIAL MOVEMENT OF SAID EXPANSION MEMBER RELATIVE TO SAID BODY MEMBER, A SPRING ELEMENT ADJACENT ONE SIDE WALL OF SAID RECESS SLIDABLY AND YIELDABLY ENGAGEABLE WITH THE SIDE WALL OF A HONING STONE FOR FRICTIONALLY GRIPPING THE HONING STONE AND MEANS CONNECTING SAID SPRING TO SAID EXPANSION MEMBER TO PREVENT AXIAL AND RADIAL MOVEMENT OF SAID SPRING RELATIVE TO SAID EXPANSION MEMBER. 